Surgical suture or ligature



Sept. 14, 1937. F, w, CARRUTHERS 2,093,145

SURGICAL SUTU RE OR LIGATURE Filed D90. 17, 19 36 IN VENT OR.

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ATTORNEY.

Patented Sept. 14, 1937 UNi'lE STATES A'iEN'i caries SUR GlCAL SUTURE 0RLIGATURE Application December 17, 1936, Serial No. 116,258

4 Claims.

The present invention relates to a ligature or suture and to a method ofpreparing the. same.

The principal object of the invention is the provision of a ligature orsuture or absorbable animal tissue of requisite tensile strength and absorptive properties, which will not have these properties adverselyaffected by heat sterilization, to devise a novel method of preparingthe same.

In the application of sutures in the repair of broken bones the materialfrequently used consists of drawn wire of stainless steel or of silvermixed with copper. Silver wire and steel wire each possessesconsiderable tensile strength, but the wire must be fastened by twistingthe ends because of the difficulty in knotting it. In employing suchmetallic sutures in holding broken or fractured bones, the wire suturesare threaded through holes drilled in the. bones and hence merely holdthe broken fragments together without providing any support to thefracture line. Even in breaks producing overlapping ends, such metallicligatures, being relatively narrow, do not support the fracture line.This constitutes the greatest disadvantage of wire sutures or ligaturesin bone surgery.

Another objection to the use of metallic sutures or ligatures is thatthe wire is not absorbable; and until such time as it may disintegrate,the metal is apt to act as a mechanical irritant to the tissues. Stillanother objection to the use of metallic wire sutures or ligatures isthat when a Roentgenray (X-ray) photograph is made of those tissues inor around which the metallic suture or ligature has been placed, suchmetallic suture or ligature is readily visible on the photographic plateor film as a foreign body. The presence of such foreign body in thetissues might result in legal action on the part of the patient againstthe surgeon for malpractice in leaving a foreign body in the tissue.

Another product commonly used in bone surgery is the kangaroo tendon,which is obtained from the tail of the small kangaroo, or Wallaby. Thetendon bundle from a freshly-killed animal is air-dried by the trapper,and then separated into the individual tendons of various diametersconstituting the tendon bundle. These individual tendons of varioussizes are used for surgical sutures and ligatures; but theirdisadvantages or limitations in bone surgery are similar to those ofmetallic wire sutures in that they merely hold broken bones together anddo not give any support to the fracture line.

It was this difficulty that suggested investigation of some. means ofproducing a surgical suture by heat sterilization and, at the same time,would have a flat, band-like portion, rather than round like a string.Such a band has many advantages and a wide field of usefulness in thosesurgical situations where it is desirable to distribute the pressure,incidental to tissue approximation, over a broad surface, and wheresupport is needed, such, for instance, as in bone surgery.

To this end, the invention contemplates in its broad aspect, a surgicalligature or suture having a band-like-or flattened central portionlength- Wise, with unflattened ends, that is, the suture or ligaturewill have a width over a suitable portion of its length so as to permitit to be wrapped one or more times around a bone fracture to lendsupport to the fracture line, the ends thereof to be tied together overthe wrapped portion to maintain the same in the proper position. Theinvention, therefore, also contemplates methods of preparing such aligature or suture.

In the drawing:

Fig. 1 is a plan View of the bandlike or flattened central portion of asuture or ligature prepared according to this invention;

Fig. 2 is a partial plan view showing an unflattened end of the sutureor ligature of Fig. 1;

Fig. 3 is a perspective View of a complete ligature or suture;

Fig. 4 is a sectional View along the line 44 of Fig. 2.

In preparing the ligature or suture of the present invention, suitableanimal tendons, such as the larger sizes of kangaroo tendons, usuallyabout 15 inches long, are first subjected to tanning by the usual orwell known chrome-tanning process as applied to animal fibers for thepurpose of delaying absorption. By varying the strength of the chemicalsused, as Well as the duration of the chrome-tanning process, the degreeof tanning may be regulated. After the chrome-tanning process, thetendons are air-dried; and their central portion lengthwise plumped bymeans of av suitable acid or alkaline bath. This central portion is thenplaced in a press having smooth or slightly roughened surfaces, whichmay be made of hard wood, metal, stone, porcelain, etc, and

sufficient pressure to produce the desired width of band I at thissection then applied, leaving the end portions 2, however, in theirround or oval condition. The greater the pressure, the wider theresulting band section. The optimum pressure is that which produces aband section of approximately one inch in width and .015 inch inthickness. This pressing process is carried out at room temperature ofapproximately 20 C., and is maintained until the band is thoroughly dry,or for approximately 48 hours.

When used in bone surgery, the primary purpose of this kangaroo band oranimal tendon band is to hold in apposition the fractured ends ofcertain types of bones. Therefore, to accommodate the various sizes ofbones, such as the radius, ulna, humerus, femur, etc., the fiat band orcentral portion of the tendons is made of various lengths, an averagebeing approximately 5 inches. The length of the band is controlled bythe length of the pressing plates. At each end of the band, there isleft in its original round or oval shape, a string-like length of tendonof approximately 5 inches. In use, the ligature may be wrapped one ormore times around the adjacent ends of the broken bones, the bandlending desirable support to the line of fracture, and the unfiattenedends then tied together to hold the ligature in place and the bonesagainst displacement.

One outstanding advantage of this ligature or suture from the surgicalpoint of view is that its physical properties are unimpaired by intenseheat. This material, therefore, readily lends itself to heatsterilization, which does not affect its tensile strength, nor itsabsorptive properties.

While the invention has been described with particular reference tospecial materials and methods of treatment, yet, obviously, I do notwish to be limited thereto, but the invention is to be construed ascovering all equivalents thereof and restricted only by the scope of theclaims.

I claim:

1. A process of making a surgical ligature or suture which'includes thesteps of softening the central portion lengthwise of an animal tendonand forming this portion into a flat band while leaving the ends thereofin an unfiattened condition.

2. A surgical ligature or suture of absorbableanimal material having acentral flattened portion and unflattened ends.

3. As an article of manufacture, a treated kangaroo tendon having acentral flattened bandlike portion, each end of which is left in itsoriginal round, string-like form and of a length sufficient to permit oftying the two ends as a ligature. a

4; As an article of manufacture, a treated animal tendon having acentral flattened bandlike portion, each end of which is left in itsoriginal round, string-like form and of a length to permit of tying thetwo ends as a ligature.

F. WALTER CARRUTHERS.

